Discussion of the Necropolis faction.

Hello everyone. I started playing the Necropolis campaign and had a question. After a battle, or somehow during a battle, does the hero replenish his army with the corpses of the fallen? For example, in Heroes of Might and Magic V, after a battle, the Necromancer replenishes his army by creating Skeleton Warriors or Archers. If so, how is this done in Heroes of Might and Magic VI?